Battery Storage Control Strategies in Microgrids: : SimulationBased Evaluation of Peak Shaving, Degradation, and CostEfficiency

Small-scale electricity grids, also known as microgrids, integrate consumption with localproduction, and storage of electrical energy. Microgrids can enhance self-consumption of locallygenerated electricity and reduce peak power demand, an increasingly vital aspect given thecapacity challenges in the Swedish power grid. The choice of control strategy for managing thebattery impacts the performance of the microgrid by altering the ability of the system to reducepower peaks, manage battery health and achieve economic viability. This thesis explores thepotential of microgrids to mitigate peak power demand through the simulation of a microgridcomprising two industrial-scale buildings, each equipped with a photovoltaic (PV) installation.Additionally, a secondary test case using load data from municipal buildings is included in theappendix to assess the generalizability of the results. Three different control strategies, each designed with a separate objective, were used to carryout the simulations. The first strategy is forecast-based, using predictions of load and PVproduction to proactively respond to expected power peaks. The second strategy prioritizesbattery health by avoiding harmful microcycling and using the battery mainly for more significantload-demand cycles. Lastly, the third strategy follows a simpler logic that maximizes the selfconsumption of solar energy on an hourly basis, without regard for forecast data or batterydegradation. The results from the simulations emphasize how each control strategy leads todifferent trade-offs between peak shaving, self-consumption, battery degradation, and economicperformance. Thus, this thesis discusses and analyzes the reasons behind the obtained resultsas well as potential strengths and weaknesses of the three different control strategies. Whencombined with an intelligent control system, microgrids have the potential to reduce powerpeaks. Thus, this study demonstrates that microgrids can play an important role in addressingcapacity challenges in the Swedish power system and that the investment can even beeconomically profitable under favorable conditions. Ultimately, the study emphasizes theimportance of aligning the control strategy with the overall goals and characteristics of themicrogrid which is crucial regardless of whether the objective with the microgrid is reducingpeak loads, maximizing solar self-consumption, or preserving battery health over time.